The untitled sequel to Avengers: Infinity War, presently dubbed Avengers 4, could not come sooner. There are a lot of questions that need to be answered and fans have already begun jotting down theories for the continuation of the storyline.
In all honesty, pretty much everything related to the upcoming sequel has been kept secret from not only the public but also the cast. That being said, breadcrumbs along the way have provided just enough understanding to presume the events to come.
Avengers: Infinity War has left the Marvel Cinematic Universe (MCU) in an incredibly bleak state. In addition to leaving behind a body count while questing for the Infinity Stones, Thanos (Josh Brolin) finally did what he wanted from the beginning — snapping his fingers with the Infinity Gauntlet to turn half of all life in the universe to dust.
Avengers 4 will pick up right after and the surviving superheroes will obviously attempt to take the fight into the second round. There are two glaring problems here that will make up majority of the plot. Firstly, just how will they defeat an overwhelmingly powerful Thanos and secondly, what about those who have perished?
The destined Iron Man
There are two popular theories about Iron Man (Robert Downey Jr.) being the central character that straightens everything out. Doctor Strange (Benedict Cumberbatch) giving up the Time Stone to save Iron Man in Avengers: Infinity War could possibly tie in with the one possible future where the Sorcerer Supreme saw Thanos defeated.
There is also the tentative matter of time travel. Since last year, there have been a few leaks from production sets that show the Avengers in their old costumes. This has led many to believe that the surviving members will be going back in time in Avengers 4 to safeguard the timeline and Iron Man will be the one to make this happen. Somehow, B.A.R.F. (Binarily Augmented Retro-Framing) from Captain America: Civil War (2016) will be involved.
The flight of Captain Marvel
The post-credits scene for Avengers: Infinity War featured Nick Fury (Samuel L. Jackson) sending an emergency signal to Captain Marvel (Brie Larson) right before turning to dust. The character is set to make her debut in the MCU just a few months before the release of Avengers 4. Hence, she is confirmed to be a major part of the upcoming sequel.
Captain Marvel is believed to be serving in deep space when Thanos goes on his rampage. She will return to Earth, possibly after picking up Iron Man and Nebula from Titan — being brought up to date in the process, and boost the friendly ranks for another fight.
Determining strength is pretty difficult within the comic books because they mostly vary with the situation on hand but Captain Marvel can definitely be considered as one of the most powerful characters in history. She just might be able to make Thanos sweat, maybe even able to rip off the Infinity Gauntlet on her own.
The seventh Ego Stone
There is a seventh Infinity Stone that is yet to be introduced by Marvel Studios. It is called the Ego Stone and contains the pure essence of an omnipotent being called Nemesis. Hence, it is incredibly powerful, perhaps even more than the other Infinity Stones combined.
In the comic books, the Ego Stone was once in the possession of Sersi, a member of the Eternals. Interestingly, Marvel Studios recently confirmed that there is a movie in the works for the Eternals for phase four. Since Avengers 4 is set to conclude phase three, an appearance by the Eternals could be expected.
Should the Ego Stone surface, who will be the right character to wield its power? It is believed that none other than Captain Marvel will be the lucky individual to become the most powerful cosmic character in the MCU.
The life inside Soulworld
For those unaware, the Soulworld was actually shown in Avengers: Infinity War — the orange sphere where a younger version of Gamora (Zoe Saldana) came up at the end. This is a pocket universe that exists inside the Soul Stone and has often been regarded as purgatory for captured souls.
It has been confirmed by co-director Joe Russo that Gamora is still alive but her soul is trapped inside the Soulworld. In that light, it can be perceived that the other vanquished souls also reside within the same dimension. Hence, everyone who perished in Avengers: Infinity War is still alive.
The problem now is bringing them back. There are only a handful of characters that have managed to escape the Soulworld in the comic books. This is where things become interesting because that short list includes Gamora.
The regretful Thanos
Thanos is unlike any other antagonist to have ever graced the MCU. He believes his destructive path to be almost noble and necessary for the longevity of the universe. While others in his place would have easily become corrupted, Thanos is not devoid of emotions, as was seen when he shed tears after realizing that the only way to obtain the Soul Stone was to sacrifice the person he holds most dear — his adoptive daughter, Gamora.
In the comic books, Thanos did everything to gain the affections of the physical embodiment of death. In Avengers 4, Gamora could possibly take that role. This does not mean that she is going to be revealed in the upcoming sequel as death herself but that she might use the opportunity to convince Thanos (in the Soulworld) to regret his decisions and gain her affections by undoing everything with the Infinity Gauntlet.
Perhaps the only solution to this mayhem is love.